If you agreed to the settlement then an appeal at this point would not get you anywhere. You would have to first find a basis to ask the trial court to set the settlement aside. Based upon the information you have provided it does not sound like you have a sufficient basis to set aside the settlement. Only after you ask the trial court to set aside the settlement would your appeal rights arise.
Generally you would have 30 days to appeal a decision denying your request to set aside the settlement. You might have up to a year to ask the trial court to set aside the settlement (again, assuming you had some basis to do so), but the more time that passes, the more difficult it becomes.